Not Applicable
Not Applicable
1. Field of Invention
This invention relates to thermal convection of heated water for domestic use, specifically to an improved and simplified controlling valve.
2. Discussion of Prior Art
The inconvenience and wastefulness of waiting for hot water to arrive at the faucet is an expense and bother. Various systems and devices have been developed to address this problem, but have had limited success.
Systems that employ pumps such as U.S. Pat. No. 5,277,219 to Lundxe2x80x94Jan. 11, 1994; U.S. Pat. No. 5,323,803 to Blumenauer Jun. 28, 1994; U.S. Pat. No. 5,511,579 to Price Apr. 30, 1996, all require an electrical source, timers, and temperature sensors, that add considerably to the cost and complexity of operation. Similar systems also waste energy by returning some heated water into the cold water plumbing.
Aspirator assisted systems such as U.S. Pat. No. 5,331,996 to Ziehm Jul. 26, 1994; U.S. Pat. No. 5,518,022 to Ziehm May 21, 1996; U.S. Pat. No. 5,622,203 to Givler et al. Apr. 22, 1997, all introduce a flow restriction into the cold water system. Also, when hot and cold water faucets are open at the same time, a portion of warmed water is introduced into the cold water system. This type of system does not work well in a one-story dwelling where the plumbing and the water heater are at the same level. Some systems recommend not insulating the return plumbing, creating an energy loss.
Basic convective flow systems, such as U.S. Pat. No. 3,929,153 to Hastey Dec. 30, 1975 and U.S. Pat. No. 5,620,021 to Hugo Apr. 15, 1997, have restrictive installation requirements. These and other past art heretofore known suffer from a number of disadvantages:
(a) The need to have upwardly sloped supply and downwardly sloped return plumbing with no sections inversely oriented.
(b) The need to have venting devices at the highest point in the system.
(c) The need to have some kind of connection between the hot and cold water systems, such as, check valves, thermostatic valves, aspirator devices, heat exchangers, and motor driven pumps.
(d) The need to have the water heater at the lowest point, preferably 5 feet or more below the faucets being served.
(e) The need to have a check valve element that is heavier than the liquid involved so as to favor a closed condition.
(f) The need to have the check valve means located at or near the water heater.
(g) Some have the need to not insulate the return portion of the convective loop.
Accordingly, several objects and advantages of my invention are:
(a) To provide a system that is not sensitive to variations in plumbing orientation, such as downward sloping portions of the supply and upward sloping portions of the return plumbing.
(b) To provide a system that does not need air venting devices.
(c) To provide a system with no connections needed between the hot and cold water plumbing.
(d) To provide a system that can have the water heater on the same level as the faucets being served.
(e) To provide a system with a lighter-than-water check valve element, so as to remain open during convective flow periods. This element to be approximately 0.95 specific gravity, so that reverse flow dynamics induces closure during hot water flow at any hot water faucet.
(f) To provide a system that can have the controlling check valve located at various places within the return loop from the hot water faucet.
(g) To provide a system that can have any amount of insulation used on both the supply and return plumbing loops.
Further objects and advantages are to provide a system that can be easily used and serviced by an average homeowner. Specifically suitable for use in a recreational vehicle (RV) where periodic servicing such as winterizing, flushing, cleaning, and filling is a necessary operation. Still further objects and advantages will become apparent from a consideration of the ensuing description and drawings.
This invention is a simplified hot water circulation system with a multifunctional flow control device that specifically addresses single level systems such as those found in recreation vehicles. The flow control device employs a movable element that is lighter-than-water which allows unimpeded flow; the flow is induced by the differential density within the water heater. This system is also readily adaptable to single level dwellings without a basement as well as multilevel dwellings.